Receptacle having at least three chambers

ABSTRACT

A receptacle for storing and subsequently mixing at least three ingredients of a product such as a dental preparation. The receptacle comprises a first chamber at one side of a perforated dividing wall, and a second and at least a third chamber at the other side of the dividing wall. A collapsible capsule adapted to form at least one of the second and third chambers comprises metal foil or compound material composed of metal foil and plastic film. A method of making such capsule includes deepdrawing and cold welding steps.

United States Patent Baumann et al. 1 1 Oct. 2, 1973 [54] RECEPTACLE HAVING AT LEAST THREE 3,190,499 6/1965 Dow 206/47 A CHAMBERS 3,415,360 12/1968 Baumann ct al. 206/47 A 3,425,598 2/1969 Kobernick 206/47 A 1 Inventors: Erwin Baumann, Nendeln; Gerhard 3,651,615 3 1972 Bohner 206/47 A Beham; l-lansjiirg Frick, both of 3,651,932 3/1972 Muhlbauer 206/47 A Schaan, all of Liechtenstein FOREIGN PATENTS OR APPLICATIONS Assgneei 'l 91,607 6/1968 France 2. 206 47 A Schaanv Llechtenste 1,180,181 2 1970 Great Britain 206 47 A 122] Filed: May 11, 1971 I Primary ExaminerWilliam T. Dixson, Jr. [2H Appl' l42236 Attorney-Christel 8L Bean [30] Foreign Application Priority Data ABSTRACT May 19, 1970 Germany P 20 24 331.6 May 19, 1970 Germany P 20 24 402.4 A receptacle for and subsequently at least three ingredients of a product such as a dental 521 us. (:1 206/47 A,'21'5/6,'206 63.5, Preparation The receptacle comprises a first chamber 1 12 72 at one side of a perforated dividing wall, and a second 51 1111. C1 B65d 81/32, B65d 25/08 and at least a third chamber at the Side the [58] Field of Search 206/47 A, 63.5, 56 AA; viding Wall- A Collapsible capsule adapted to form at 215/12, 6; 128/272; 220/205, 23; 222/145 least one of the second and third chambers comprises metal foil or compound material composed of metal 5 R f r Cited foil and plastic film. A method of making such capsule UNITED STATES PATENTS includes deep-drawing and cold welding steps. 1,077,835 11/1913 Kelly 206/47 A 5 Claims, 13 Drawing Figures PATENIEDW 2 SHEET 30F 5 INVENTOR.

um N hr R meF O uB a 9 T Bdr T rnO .mma A Wrn rea EGH mm-m 3.762.540

SHEET 50F 5 INVENTORS Erwin Baumann Gerhard Beham V Hans org Frlck ATTORNEYS RECEPTACLE HAVING AT LEAST THREE CHAMBERS This invention relates to receptacles having a plurality of chambers.

It has been proposed heretofore to provide multichamber receptacles for initially separately storing and subsequently mixing a plurality of ingredients to make a product such as a dental preparation ready for use, the ingredients being capable of reacting upon each other. Individual chambers of prior deviceshave been separated by an easily destructible membrane; and the receptacle parts forming the chambers have been slidably arranged relative to each other. Instead of employing a membrane, a bag-shaped or tubular storage means may be provided for receiving one of the components and may be positioned in a hollow cover of the receptacle, the storage means being formed, e.g., by a closed, preferably welded pouch of flexible sheet material. In this type of arrangement, the pouch abuts a perforated dividing wall disposed between the chambers and is arranged to be ruptured upon movement of certain parts of the receptacle towards each other, whereby a connection will'be established between individualchambers so that the respective ingredients or substances will contact one "another.

' I The pouch which is preferably filled with a liquid or When boththe pulverulent substance and the liquid or pasty substance are-present in the mixing chamber,

a thorough mixing operation is carried out, which is preferably achieved by inserting the receptacle in the fork of an automatic,- oscillatingmixer, i.e., a so-called amalgam mixer. a It has further been proposed-that in-a receptacle having perforated dividing wall means two pouches be provided and ruptured so that two liquid; or pasty substances may be used. However, this-proposal relates to a structure wherein for receiving the secondpouch an additional hollow'cover'is located at theend of the mixing-chamber oppositeto the end where the usual cover and pouch are disposed so that a symmetrical or mirror-picture 'arrangementwill be obtained.

In the case of such symmetrical arrangement of pouches it will normally be necessary toapply pressure twice to .the receptaclet'or establishing contact between the two liquid'or pasty substances and the pulverulent substance stored'in the mixing chamber. First one pouch is rupturedby applying pressure to the top cover, hereupon the receptacle is turned through [80 and then the other pouchis ruptured by applying pressure to the other cover. Only after the walls of both chambers containing liquid or pasty substances have thus been forced open and all the ingredients are present in the mixing chamber, it will be proper toshake the receptacle mechanically and thereby mix the substances thoroughly.

If liquid substances are stored in upper portions and lower portions of the receptacle and pressure is applied at the top and bottom simultaneously, the liquid substance contained in the bottom part must be injected into the pulverulent substance from below and must thus be caused to rise against the action of gravity, whic sule suitable for the separate and prolonged storing of often results in faulty operation.

It is an object of the invention to improve'a receptacle having a perforated dividing wall so that a preferably pulverulent substance deposited in a mixing chamber and two or more preferably flowable substances may be combined and subsequently mixed in a simple manner by a single application of pressure at one end of the receptacle only. M

As stated, pouches of flexible sheet material have been provided in prior receptacles-to store liquid sub stances. In the case of solutions having a low vapor pressure or of aqueous solutions, it has been found entirely satisfactory to use pouches made from a film of plastic such as polyethylene, or from compound-sheet material comprising different plastics and, if suitable, one or more layers of metal, the liquid substances being enclosed by welding the sheet material. In the case of organic solvents or monomers capable of being polymerized or substances having higher vapor pressures or substances liable to decompose, however, pouches-of the foregoing type will last only for a limitedstorage time since these liquid substances tend to dissolve the film material, to separate the laminae of compound sheets, to impair the formation of satisfactory seams, and to penetrate welded seams, Of course, it is possible to store such-liquid substances in an easily destructible glass ampoule or sphere and to close the vessel by welding the glass along theseams, but such glass vessels'are 'often damaged during shipping and, moreover, after the vessel has been destoryed to release the contents, glass particles must be removed before the liquid substance or substances are mixed with, the pulverulent substance. In certain cases itwill even be necessaryto separate the liquid ingredient from glassparticles by means of a centrifuge,that is, an additional step-will be required. v V 3 Further difficulties are encounteredif two substances capable of reacting upon each other have to be stored separately in a mixing receptacle for an extended period of time and these substances eitherhave relatively high vapor pressures or tend to damage filmconsisting of plastic. In case two pouches of such plastic are used, they must be spacedfron each other in the'mixing receptacle as far as possible, zwhichzwill complicate the design of the receptacle, It would not be possible in the case of'such substances to usea duplex pouch having an intermediate wall of plastic film since the substances would diffuse'through the film and'wouldthen react upon each other, i Y

It is a further object of the invention, therefore, to provide a receptacle and an improved collapsible cap one or more preferably flowable substances which tend to dissolve plastics or have a relatively high vapor pressure, or which are liable to decompose or'prevent the formation of a satisfactory welding seam in common plastic film. 1

It is an additional object of the invention toprovide an effective and economical method of making the improved collapsible capsules.

To introduce a plurality of preferably, flowablesubstances into a main or first chamber from the same-area through a perforated dividing wall, the receptacleaccording to the invention comprises a base member having the main or first chamber therein for receiving a first, preferably pulverulent substance; a dividing wall extending generally across the base member and having an opening therein, one lateral face of the dividing wall limiting the first chamber; hollow means carried by the base member for forming a cavity adjacent to the other lateral face of the dividing wall; and insertable means in the cavity for forming at least a second and a third chamber adapted to receive at least a second and a third substance, respectively, at least one of the second and third substances being flowable; and at least one of the hollow means and insertable means being operable to connect the chambers so as to permit passage of at least the second and third substances from the second and third chambers through the opening of the dividing wall into the first chamber for admixture to the first substance.

The cavity of the hollow means may be closed towards the outside by a movable cap or a ram, and the second and third chambers may be arranged in two separate members, each of which has at least one frangible wall, or in a duplex member having at least two frangible walls. Upon advance of the movable cap or ram in the direction towards the dividing wall, the frangible walls will be ruptured and the chambers will be interconnected, the volume of the second and third chambers being reduced to a negligible amount. Advance of the cap may be obtained by a sliding movement along a straight path or by turning the cap if the latter engages the base member or the dividing wall by means of screw threads. The dividing wall may be connected to the base member so as to be stationary relative thereto or may be movable therein or, if desired, may form a unit with the base member.

To reduce the volume of at least the second chamber to practically zero, cooperating faces of the cap or ram and the dividing wall should be mutually substantially complementary, i.e., the profiles thereof should be substantially identical.

. The material of the receptacle should have a stiffness sufficient for mounting the receptacle in a vibrating mixer or the like.

To facilitate the discharge of flowable substances from the second and third chambers, a weakened, breakable portion is provided at least in a chamber wall which abuts the perforated dividing wall. weakened, breakable portions may further be arranged in wall means between separate members having the second and third chambers therein or in an intermediate wall of a duplex member, the breakable portions being preferably disposed in opposite wallsand at the largest possible distance from each other.

In one embodiment of the invention the second chamber is formed by a collapsible capsule and the third chamber is positioned in a sleeve-like member having a rupturable bottom, the capsule being preferably positioned between the sleeve bottom and the perforated dividing wall. The sleeve bottom may either be thinner than the side wall of the sleeve to serve throughout as a breakable portion or may have a weakened, breakable portion therein. Preferably, the wall of the capsule facing the sleeve bottom is likewise provided with a weakened, breakable portion.

lfa ram is employed, a tight closure towards the outside may be achieved by means of sealing rings or by a cover to prevent leakage of an enclosed flowable substance during shipping or storage.

The second and third chambers are preferably arranged in superimposed relationship.

In another embodiment of the receptacle according to the invention, a removable closure mean such as a cover or cap is provided at the end of the first or mixing chamber remote from the second and third chambers.

Further, the perforated dividing wall between the first or mixing chamber and the other chambers may be in the form of a pistonlike member movable approximately from one end of the first chamber to the other end which in this case is normally closed by a removable cover or provided with a normally closed, nozzleshaped extension. The cover will be removed or the extension will be opened after the ingredients have been mixed. To avoid movement of the pistonlike member into the first chamber during ram advance, it is preferable to provide either an outer bead-like projection on the circumference of the pistonlike member at the initial border between the first and second chambers or an inner bead-like projection on the interior wall of the first chamber at the same border. If an outer projection on the pistonlike member is employed, a circumferential groove may be arranged in the interior wall of the first chamber for engagement with the projection. instead of providing an integral projection, the crosssection of the pistonlike member may be enlarged by means of an inserted stop ring which is adapted to engage the upper edge of the base member and is removable to permit advance of the pistonlike member into the first or mixing chamber.

Furthermore, movement of the pistonlike member during ram advance may be prevented simply by compressing the base member from the outside.

If a nozzle-shaped extension is provided at the lower end of the first or mixing chamber, the receptacle according to the invention may be used as a syringe for applying the mixed contents of the first chamber directly to the desired area. For example, a dental cement or a filling comprising an artificial resin may be injected directly into a tooth cavity.

In the case of such arrangement it is desirable to close the nozzle-shaped extension during the mixing operation, that is, to carry out the mixing step only in the first or mixing chamber proper having a crosssectional area larger than that of the interior of the extension, which will assist in avoiding the formation of an inhomogeneous mixture. The nozzle-shaped extension may be closed either by a portion of the bottom of the mixing chamber which will be pierced after the ingredients have been mixed, or by a plug or pin which will be pulled out of the extension after the mixing operation. In simple cases, however, it will be sufficient to provide a nozzle-shaped extension, the interior of which communicates with the mixing chamber, and which has a closed outer tip and may be integral with the base member. It will then be necessary merely to cut off, break off, or pierce the tip of the extension after the ingredients have been mixed.

Apart from ease of manipulation, the receptacle according to the invention is advantageous in that its structure is simpler and less expensive than that of prior devices, and the individual parts can be more easily assembled in mass production.

Moreover, the receptacle according to the invention may be shaped so that it is mountable in a syringe as an insert or a cylindrical ampoule and after its use only the corresponding, relatively simple mixing receptacle need be discarded, but not the more expensive injecting means.

in the case of substances such as flowable ingredients which tend to dissolve sheets of plastics or have a relatively high vapor pressure or cause related difficulties, the walls encompassing the second and third chambers comprise flexible metal foil or combinations of metal foil and plastic film arranged so that the substances referred to will contact metallic surfaces.

in particular, the collapsible capsule according to the invention includes base wall means, and complementary wall means, at least one of the wall means having a concave portion facing'the other wall means. The

wall means comprise metal foil and are secured to each other along their edges by cold welding so as to form an approximately lenticular body having a chamber therein; and a weakened, breakable portion is provided in at least one of the wall means.

As mentioned hereinbefore, weakened, breakable portions serve to facilitate the discharge of substances from the second and third chambers. In addition, it is acheived that upon application of pressure the respective walls will rupture in the desired areas and not at a welded seam or at some other point, which could jeopardize proper quantitative mixing of dosed substances. The mixing of substances in predetermined proportions is essential to ensure the desired quality of dental fillings or other dental preparations.

in the case of compound sheets comprising metal foil and plastic film, it is important that welding will take place at a metallic side or portion since welding at a plastic or film side would again result in the difficulties encountered when using plain plastic film.

It was unexpected that cold welding would suffice to render collapsible capsules entirely fluid-tight. Any heating of the capsule had to be avoided in view of the likelihood of the formation of high vapor pressures inside the capsule and in view of the heat-sensitivity of certain substances to be stored.

A particularly suitable suitable material for outer and intermediate walls of the second and third chambers is aluminum or copper foil which may have a wall thickness of approximately to 200 ;1., preferably approximately 40 to 100 If aluminum foil is used, the latter may be oxidized at least in part and the arrangement should preferably be such that a bright and an oxidized aluminum surface or two oxidized aluminum surfaces contact each other where cold welding takes place. The oxidation of the aluminum surfaces is preferably effected by an anodic treatment which is also called eloxation.

When two metal bodies are united bycold welding, metal particles of one body penetrate the other body and vice versa, whereby a completely vapor-tight bond of practically unlimited durability will be obtained. The mechanical strength of the bond may be still further increased by providing the cold welded seam with a beaded edge.

in the case of a duplex capsule the two individual chambers which are separated by a common intermediate wall may be of equal size so that the capsule will have the shape of a biconvex lense. However, preferably one of the chambers is partly encompassed by the other chamber. A weakened, breakable portion or a plurality of such portions in the intermediate wall or walls may be located opposite one or more weakened. breakable portions in one or more of the outer walls. Preferably, weakened, breakable portions in intermediate walls are disposed at the maximum possible distance from each other and from any weakened, breakable portion or portions in the nearest outer wall. Thereby, unimpaired flow or passage of the second and third substances will be obtained when the collapsible capsule is compressed.

Pulverulent substances suitable for deposit in the first or mixing chamber are, for example, powdered plastics such as pearl polymerisates of acrylic and/or methacrylic acid esters or copolymers thereof of the type used for making fillings, crowns or inlays, and further powdered materials conventionally used for making dental cements, e.g., zinc oxide, silicate cement powder or mixtures of such substances. instead thereof, however, the mixing chamber may contain a liquid or pasty substance if suitable.

Flowable substances suitable for deposit in the second and/or third chambers include liquids, pasty materials, and even materials which are solid at room temperatures. Suitable liquid substances comprise organic liquids such as mentioned hereinafter; and, e.g., phosphoric acid solutions. Suitable pasty substances include mixtures of monomers and polymers or copolymers, e.g., of acrylic or methacrylic acid esters. Furthermore, suitable substances which are solid at room temperatures are, for example, higher esters of acrylic or methacrylic acid, e.g., monomeric acrylates or methacrylates of higher molecular weight; and organic peroxide catalysts having an organic radical of higher molecular weight. in the case of a substance which is solid at room temperatures, it is appropriate to melt such substance by heating the receptacle before the mixingstep is carried out.

As indicated hereinbefore, the receptacle according to the invention is adapted in particular to accommodate flowable substances which, when enclosed by common sheets of plastics or by simple compound sheets composed of metal foil and plastic film, would be storable to a limited extent only sinve they tend to dissolve such plastics or have a high vapor pressure or prevent the formationof satisfactory welded seamsin such plastic material. I

Heat-sensitive and/or volatile substances, i.e., substanes which even at normal temperatures have a relatively high vapor pressure, belong to the foregoing type and include, for example, organic solvents; liquid monomers capable of, being polymerizedv as used in dentistry for making fillings of plastics, crowns, and in.-

lays; certain catalysts; and so forth. Monomers capable of being polymerized may have olefinic double bonds. Likewise storable in the receptacleaccording to the in.- vention are solutions of polymers in organic solvents, mixtures of activators, and additions as used in triple.- component systems of plastics. Other fluid substances which have no high vapor pressure but tend to impair sheets of plastics or to damage welded seams connect:- ing plastic sheets, may likewise be enclosed in the collapsible capsules according to the invention in avaportight manner. This type of substances includes ethereal oils such as used in dentistry, e.g., eugenol, bergamot oil, and clove oil.

if, for example, the receptacle is to be employedfor making plastics such as used in dental fillings, dentures, crowns, and inlays, the first or mixing chamber may stance from the second chamber positioned next to the perforated dividing wall. For example, a pasty substance or even a pulverulent substance present in the second chamber may be practically completely removed therefrom in this manner.

If, for example, the third chamber remote from the dividing wall contains a liquid monomer capable of being polymerized, e.g., a monomeric acrylate or methacrylate as referred to hereinbefore, the second chamber disposed next to the dividing wall may contain a substance acting upon the monomer or reacting therewith, the monomer serving as a rinsing liquid when passing through the second chamber. Substances acting upon the monomer are, e.g., catalysts which may be in the form of a solution or suspension, such as peroxide catalysts. Substances which react with the monomer are, e.g., other monomers such as monomers having a viscosity higher than that of the monomer in the third chamber.

The invention further includes an effective method of making collapsible capsules as set forth later.

Other objects, features and advantages of the invention will become apparent as the description proceeds.

In the drawings which illustrate several embodiments of the invention by way of example, and on an enlarged scale,

FIG. 1 is a longitudinal section through a receptacle according to the invention;

FIG. 1A is a similar section showing the parts in another position;

FIGS. 2 to 5 show longitudinal sections through modified receptacles;

FIGS. 6 and 7 show modifications of the lower end of the receptacle according to FIG. 5;

FIG. 8 illustrates a method of manufacturing a collapsible capsule according to the invention and shows the capsule as positioned at the completion of the process;

FIG. 9 is a plan view taken in the direction of arrow 9 in FIG. 8;

FIGS. 10 and 11 are fragmentary sections showing portions of FIG. 8 on a larger scale; and

FIG. 12 is a fragmentary section showing a modified detail.

The embodiments shown in FIGS. 1 to 7 are provided with three chambers, but it will be clear that further chambers may be added if desired, e.g., by using amulti-chamber collapsible capsule having more than one intermediate wall.

A collapsible capsule of the duplex type is employed in the embodiments of FIGS. I to 3 and 8 to 12, whereas the embodiments of FIGS. 4 to 7 are provided with a single-chamber collapsible capsule.

Referring now to FIGS. 1 and 1A in greater detail, the receptacle illustrated therein comprises a hollow base member or container generally indicated at 20 and shown in upright position. The base member is made from a relatively rigid material, e.g., a stiff body of plastic such as polypropylene, and includes a handle portion 21 and a generally hemispherical wall 22 forming the bottom ofa first or mixing chamber M. A dividing wall 23 having an opening 24 therein extends across the base member 20 and freely rests thereon at the upper end thereof, the lower end of the dividing wall being removably inserted in the base member. The perforated wall 23 has an upper side or upper lateral face 25 and a lower side or lower lateral face 26 which limits the first or mixing chamber M and is generally of hemispherical shape so as to conform to the shape of wall 22 of the base member. Thus, chamber M has an approximately spherical shape which will facilitate the mixing operation. A hollow means in the form of a movable cap 28 is carried by base member 20 and has a cavity C therein which is disposed adjacent to the upper lateral face 25 of the dividing wall. Cap 28 extends over the dividing wall 23 and base member 20 at the upper end of chamber M and is provided with an internal abutment face 29.

Arranged in the cavity C is an insertable, frangible means which in this embodiment comprises a collapsible duplex capsule generally indicated at 30, the capsule enclosing a second chamber generally indicated at S and a third chamber generally indicated at T. The chambers S and T which form subchambers of the capsule are arranged in superimposed relationship. Capsule 30 which has an approximately lenticular shape is composed of three sheets or walls, that is, an outer, relatively flat bottom sheet or base wall 31 which abuts the upper face 25 of wall 23 and has a weakened, breakable portion or web 32 therein, and the contour of which is complementary to the contour of the upper face 25 of wall 23; a dish-like or bowl-shaped intermediate sheet or wall 33 which is flat at the top and initially sepatates the chambers S and T, but has a weakened, breakable portion or web 34 therein; and an outer, calotte-shaped top sheet or wall 35 which has no weakened portion therein, and the contour of which is adapted to cooperate with the contour of the internal abutment face 29 of cap 28. Breakable portion or web 32 which registers with the opening 24 of wall 23 is slightly thinner than breakable portion or web 34 as best shown in FIGS. 10 and 11. The walls 31, 33, 35 may consist, e.g., of aluminum foil, and are preferably joined along their edges by cold welding. As stated hereinbefore, coompound sheets may be used if desired.

In more general terms, it may be said that capsule 30 comprises base wall means 31, and complementary wall means cooperating with the base wall means, at least one of these wall means having a concave portion for forming the chamber S in conjunction with the other wall means. The base wall means 31 represents one outer wall of the capsule; and the complementary wall means comprise the intermediate wall 33 facing the base wall means at one of its sides, and the additional outer wall 35 cooperating with the other side of wall 33, the walls 33, 35 being shaped so that they will conjointly form the chamber T.

A first, preferably pulverulent substance or ingredient 36 is provided in the chamber M while second and third substances or ingredients 37 and 38 which differ from each other are deposited in the second and third chambers S and T, respectively. At least one, and preferably both of the second and third substances 37 and 38 are flowable.

In the position according to FIG. 1 the capsule is securely held in place since edge 39 thereof is positioned between cap 29 and dividing wall 23 and the top of the capsule is engaged by the abutment face 29 of the cap.

Cap 28 is operable to contact individual chambers in the following manner. When the cap is moved in the direction towards the perforated wall 23 to apply pressure to capsule 30, the breakable portion 32 which is slightly thinner than portion 34 will rupture first and the flowable ingreidient 37 will then be injected into the mixing chamber M. Thereafter, the breakable portion 34 will rupture; and the flowable ingredient 37 will be caused to pass from chamber T through chamber S taking residues of the ingredient 37 along and will then likewise be injected into chamber M.

After cap 28 has been moved downward as far as possible and, thereby, the capsule 30 has been compressed, the parts are in the position shown in FIG. IA. Central portions of sheets 31, 33 now protrude into the opening 24 as indicated at 31, 33', and a portion of sheet 35 has been pushed upwardly as shown at 35 while the volume of chambers S and T has been reduced to a negligible amount which is practically equal to zero. To obtain such reduction in volume, the internal abutment face 29 of cap 28 and the upper lateral face 25 of wall 23 are substantially complementary to each other over a predetermined area, that is, except in the region where a space is required'for pushing the portion 35 of sheet 35 upwardly.

When all the required ingredients 36, 37, 38 are present in chamber M, the receptacle may be placed in an oscillating mixer. After the mixing operation has been completed, the cap 28, the compressed sheets of foil 31, 33, 35, and the loosely inserted wall 23 will be separated from base member and the finished product may then be removed from chamber M.

As the second and third chambers S and T are disposed in the common cavity C and thus are arranged at the same end of the receptacle, it is achieved that by a single depression of cap 28 both flowable substances 37 and 38 will be injected through the dividng wall 23 into the mixing chamber M in an improved manner.

It shouldbe noted that the path of travel of cap 28 coincides with the longitudinal direction of the receptacle which is of elongated shape so that advance of the cap from the position of FIG. 1 will result in a reduction in length of the receptacle. In the position of FIG. 1A, the internal abutment face 29 of the cap operatively engages the upper face of wall 23 and thus serves in conjunction with wall 23 as a means for preventing further advance of the cap and any further reduction in the length of the receptacle after the required pressure has been exerted upon capsule and the breakable portions thereof.

Further, it should be noted that the two breakable portions 32, 34 positioned in the opposite walls 31, 33 are located approximately in an area in which these walls are initially spaced a maximum distance from each other.

Instead of mounting cap 28 for sliding movement, the cap may be connected to the base member by means of screw threads.

-Referring to the embodiment shown in FIG. 2, the upper portion of the receptacle corresponds to the arrangement shown in FIG. I and the same reference numerals are used to indicate identical parts. A short base member 50 is removably inserted in a dividing wall 53 and encloses the mixing chamber M in conjunction therewith. The dividing wall 53 has an opening 54 therein and is provided with a lower extension 57 to accommodate the base member. After the mixing operation has been completed, the base member 50 may be separated from the upper portion of the receptacle for easy removal of the finished product.

In FIG. 3, the lower portion of the receptacle is similar to the arrangement of FIG. 2 in that the base member 60 is relatively compact and may be easily separated from the remaining structure for removal of the finished product. However, the upper portion of the receptacle is of a different type in that the required dividing wall and the hollow means form a unit generally indicated at 62, which is supported on base member 60 at the upper end of the latter. Unit 62 includes a dividing wall portion 63 provided with an opening 64, and a sleeve-like portion 67 which represents the required hollow means and has the cavity C therein, the lower or inner end of the cavity being defined by the upper face 65 of dividing wall portion 63.

In this embodiment, the insertable means includes a movable ram 68 introduced into cavity C from the re.- mote upper or outer end of the latter. Ram 68 is provided with an abutment face 69, the function of which is similar to that of the internal abutment face 29 of cap 28 in preceding embodiments. A collapsible duplex capsule 30 to 35 of the type described is located between wall portion 63 and ram 68.

As indicated at 70, the sleeve-like portion 67 has a slight internal bead-like projection therein and ram 68 has corresponding outer projections 71 on its circumference. These projections which are shown in an exagerated manner for better illustration serve to engage each other in the initial position indicated in FIG. 3 to prevent undesired movements of the ram during storage of the ingredients 36, 37, 38. When at the start of a mixing operation a substantial pressure is applied to the ram, however, the limited resistance at the slight projections will be overcome so that the ram will descend to rupture capsule 30. The operation will then continue in the manner set forth in connection with FIGS. 1 and 1A. It will be clear that in embodiments of this or similar type the insertable means which includes a movable ram is operable to connect the chambers.

FIG. 4 illustrates an embodiment wherein'only the second chamber is located in a collapsible capsule, while the third chamber is arranged in a different manner. Referring to details of this embodiment, a base member having an upper abutment face 81 carries a unit generally indicated at 82 which includes a dividing wall portion 83 provided with an opening 84 and with an upper lateral face 85, and which further includes a sleeve-like portion 87 having a cavity C therein so that with regard to parts 80 to 85 and 87 the structure is similar in principle to the arrangement shown in FIG. 3. The lower or inner end of the cavity is again defined by the upper face 85 of wall portion 83, but the remaining parts of the receptacle are of a differ.- ent design.

The insertable means includes a single-chamber capsule generally indicated at 90 which is located in cavity C and encloses the second chamber S. Capsule 90 corresponds to the lower portion of the duplex capsule 30 in FIGS. 1 to 3, except for the shape in the peripheral area, and is composed of two flexible sheets comprising foil, that is, a bottom sheet or base wall 91 abutting the upper face 85 of wall portion 83 and having a weakened, breakable portion 92 therein; and a top sheet or complementary wall 93 having a weakened, breakable portion 94 therein, the walls being connected along their edges, preferably by cold welding. At least one of the walls 91, 93 has a concave portion for forming the chamber S in conjunction with the other wall.

Further, the insertable means includes a movable, hollow ram generally indicated at 96 which is telescoped in cavity C from the remote upper or outer end of the latter and has a third chamber T therein in superimposed relationship to chamber S. Ram 96 which may consist of flexible material such as flexible sheet aluminum, is provided with a sleeve-like portion 97 and a bottom 98 positioned at the lower end of the ram. Bottom 98 faces the dividing wall portion 83 and has a straight abutment face 99 of a shape complementary to that of the straight upper face 85 of dividing wall portion 83, the function of the abutment face 99 being similar to the function of the abutment face 69 of ram 68 in FIG. 3. A weakened, breakable portion 100 in bottom 98 is aligned with the upper breakable portion 94 of capsule 90.

Furthermore, the insertable means includes a piston 102 introduced into the hollow ram 96 from the upper or remote end thereof so as to close chamber T' towards the outside, the piston being provided with sealing rings 103.

When piston 102 is moved downward, pressure will be applied to the flowable ingredient 38 in chamber T and will also be transmitted through bottom 98 of ram 96 to capsule 90 and to the flowable ingredient 37 in chamber S. The breakable portion 92 which registers with the opening 84 is somewhat weaker than the other breakable portions and will rupture first to start injection of ingredient 37 through opening 84 into the mixing chamber M. The aligned breakable portions 94 and 100 will then rupture approximately at the same time and the flowable ingredient 38 will be caused to pass through the second chamber S before entering chamber M, whereby the chamber S may be rinsed. The preferably flowable ingredients 37, 38 will then be mixed with the preferably pulverulent ingredient 36 in chamber M.

It will be apparent that during the downwardly directed advance of piston 102, the hollow ram 96 will likewise move downward though the distance travelled by the hollow ram will be shorter. When the piston and the hollow ram have been depressed as far as possible, the volume of chambers S and T will have decreased to a negligible amount. The volume of cavity C will likewise be reduced and will be practically zero since the flexible material of ram 96 will contact adjacent surfaces smoothly and substantially tightly.As the unit 82 rests on the abutment face 81 of base member 80, it is prevented from moving downward relative to the base member during descent of ram 96 and piston 102.

FIG. illustrates an embodiment wherein the base member is provided with a releasable closure means positioned at the bottom of the mixing chamber, and the unit designated 82 in FIG. 4 has been modified so as to be movable for expelling the finished product. Referring to the details, the receptacle comprises a base member generally indicated at 110 which is provided with a tubular side wall 111 surrounding the chamber M; an upper face 112; and a bottom 113. Attached to bottom 113 is a nozzle-shaped extension 114 which is initially closed by a relatively thin bottom portion 115. A cannula 116 may be connected to the extension 114 by screw threads as shown.

A pistonlike unit generally indicated at 120 includes a dividing wall portion 123 provided with an opening 124, and further includes a sleeve-like portion 127 having the cavity C therein. Unit 120 is advanceable in the tubular side wall 111 to the lower end of chamber M. The sleeve-like portion 127 has an outer, circumferential groove 128 therein to receive a removable split ring 129 for engagement with the upper face 1 12 of the base member.

Other parts of the receptacle correspond to respective parts shown in FIG. 4, and the mixing operation is carried out in a corresponding manner. While the mixing step proceeds, the split ring 129 will serve as a stop means for securing the unit 120 against movement relative to the base member in the direction towards the lower end of chamber M. Upon completion of the mixing operation, the thin bottom portion will be pierced from below by means of an elongated tool and the split ring 129 will be removed. The pistonlike unit may then be advanced to the lower end of the mixing chamber to expel the finished product through extension ll4 and cannula 116. Accordingly, the receptacle may be used as a syringe to apply the finished product such as a ready dental preparation directly to the desired area.

Instead of employing a split ring as a stop means, the pistonlike unit 120 may be provided with a bead-like projection at its lower end for engagement with an internal groove in the upper portion of tubular wall 111, or the upper portion of wall 111 may have an internal bead-like projection and the unit 120 may be provided with a groove in analogy to the arrangement shown at 70 in FIG. 3. In certain cases it will be sufficient simply to compress the tubular wall 111 from the outside to prevent the unit 120 from descending to the bottom of chamber M prematurely.

FIG. 6 illustrates a modification of the lower portion ot the receptacle of FIG. 5. The modified embodiment includes a base member having a nozzle-shaped extension 141 which is open at the top and closed at its lower tip 142. This modification is suitagle in particular for mixtures of low viscosity since in the case of such material the relatively narrow space within extension 141 which communicates with chamber M will not give rise to any difficulties during the mixing procedure. To discharge the ready product, it is merely necessary to cut off, break off, or pierce the tip 142. This modificed structure is very simple and relatively inexpensive.

The receptacles according to FIGS. 5 and 6 may be used as inserts for conventional syringes.

Instead of employing a fixed bottom having a nozzleshaped extension thereon, the modified base member shown in FIG. 7 is provided with a removable bottom or cover 151 which is inserted in the base member at the lower end thereof so that there is some similarity to the manner in which the base member is inserted in the extended dividing wall in FIG. 2. The upper portion of the modified receptacle corresponds to the arrangement illustrated in FIG. 5. After the mixing operation has been completed, bottom or cover 151 will be pushed out of chamber M together with the finished product which may again be a ready dental preparation. It should be noted that the inserted bottom 151 may be replaced by a snap cover bearing against the lower end face of base member 150, or by a cap engaging the outer circumference of the base member either frictionally or by means of screw threads.

As stated, the receptacle may be clamped in the fork of an automatic oscillating mixer (frequency range about 3,500 to 10,000, preferably 4,000 to 7,000, oscillations per minute), whereby a homogeneous mixture will be obtained within a few seconds. If desired, the mixing operation may be performed in a vacuum. To

this end, the receptacle may be enclosed in an outer capsule which will be evacuated.

Referring now to the method of making a collapsible capsule according to the invention, the manufacture of a duplex capsule will be described first.

The duplex capsule generally indicated at 30 (FIGS. 8 and 9) is made from metal foil, e.g., aluminum or copper foil, or from compound sheet material composed of metal foil and plastic film. A material should be selected which is capable of being deep-drawn, and which has a wall thickness of to 200 a, preferably 40 to 100 '1,- At the start, a blank of such material is deep-drawn to produce a depression or concave portion forming the subchamber T which may be of hemispherical shape. The resulting, calotte-like outer wall 35 is placed on a support 160 with the concave portion facing upwardly, see FIGS. 8 and 9. A measured amount of preferably flowable ingredient 38 is deposited in subchamber T by means of a pipette or micropipette or the like.

An additional blank of the selected material and of a size sufficient to cover wall 35 is then deep-drawn to obtain a depression which forms the subchamber S, and the depth of which is smaller than the depth of subchamber T, whereupon the weakened, breakable portion 34 is produced by a pressing step or another suitable procedure, the breakable portion 34 being preferably located as low as possible within the depression or subchamber S. The resulting intermediate wall 33 is placed upon the outer wall 35 so that the subchamber T faces upwardly and the subchambers S and T are aligned with each other. The edges indicated at 39 are connected and sealed in a fluid-tight manner by cold welding which is performed either under pressure (at about a few thousand kg/cm) or by means of ultrasonic vibrations. Metal-to-metal contact should be established before welding, i.e., the welding should be performd at a metallic face or portion in the case of compound sheets composed of metal foil and plastic film. Subchamber S is then supplied with a measured amount of the preferably flowable ingredient 37 which may be a solution of an activator, catalyst, or accelerator as used in the polymerization of plastics.

A further blank consisting of the afore-mentioned selected type of material and having a size sufficient to cover wall 33 serves as the outer wall 31 and is provided with the weakened, breakable portion 32. Wall 31 is placed upon the intermediate wall 33 in aligned relationship and is secured thereto and sealed along the edges of the walls by cold welding in the manner described in connection with walls 33 and 35. As shown in FIG. 8 and indicated hereinbefore, each wall 31 may have an impressed shape complementary to the shape of the upper face (FIG. 1) of dividing wall 23 upon which the wall 31 will rest when the receptacle is assembled.

Care should be taken that the faces to be welded are perfectly clean, free from oil and grease, and not spattered during the pouring of liquid ingredients into the subchambers.

The weakened breakable portions may be arc-shaped and may extend along about three quarters of the periphery of a circle as shown at 32 in FIG. 9, or may be star-shaped or have any other suitable form.

FIGS. 10 and 11 which represent enlarged portions of FIG. 8 show sectional views of the breakable portions or webs 32 and 34, respectively, the breakable portion or web 32 of outer wall 31 being thinner than the portion or web 34 so that web 32 is adapted to rupture first.

If it is desired to produce a capsule having more than two subchambers, one or more additional intermediate walls are placed upon the intermediate wall 33 and secured by welding before the outer wall 31 is attached to the structure.

For mass production, a plurality of capsules may be manufactured simultaneously. The chain lines in FIG. 8 indicate one additonal capsule at 30 and an extension of the support at 160. A relatively large strip of selected metal foil or foil combined with plastics is preferably used as the starting material. For example, the width of the strip may range from 20 to 120 mm while the strip may be up to 10010 200 m long. If the strip is 120 mm wide, three depressed sections or calotte-shaped outer walls 35 of 40 mm diameter each may be produced next to each other, e.g., in staggered arrabgement. Similarly, six calotte-shaped sections or walls may be accommodated next to each other in a strip of the same size if the diameter of each wall amounts to only 20 mm. A measured amount of the preferably flowable ingredient 38 is deposited in the depressions or subchambers T of the individual sections or walls 35 in the manner described in principle in connection with FIGS. 8 and 9, the depressions T facing upwardly. An intermediate strip of the selected material is then provided and a predetermined number of complementary sections or walls 33 including breakable portions 34 are produced therein at a distance from each other equal to the distance between thesections or walls 35 produced in the first-mentioned strip. The intermediate strip is superimposed uponthefirstmentioned strip so that each wall 33 forms a pair with cover sections or outer walls 31 therein at the required spacing and also includes a corresponding number of breakable portions 32, is then placed upon the intermediate strip with the cover sections or walls 31 being aligned with the sections or walls 33. The three superimposed strips are indicated by a chain line 162 in FIG. 8. Coordinated sections 31 and 33 are connected by cold welding and the resulting capsules may then be separated from each other by stamping. Though it is preferred to perform the stamping operation as the last step of the process, individual sections 31, 33, 35 may be separated from the respective strips of material immediately upon deep-drawing or pressing, or at any other suitable, intermediate stage of the method if desired, and may then be connected to each other after the required substances have been deposited in the respective chambers.

To manufacture a single-chamber capsule of the type shown at 90 in FIG. 4, the procedure will be the same in principle as set forth in connection with FIGS. 8 and 9, but the calotte-shaped outer wall 35 will be omitted. Accordingly, the method will start with a blank for forming the wall 33 in FIG. 8 and otherwise will be completed in the manner described, except for the fact that the edge of the capsule will be shaped as shown in FIGS. 4 and 5.

Of course, a single-chamber capsule may also be obtained by starting with a blank for the outer wall 35 as described and terminating the procedure after the wall 33 has been welded to wall 35. In this case, wall 33 may be flat or may have any other desired shape.

Referring to the modification shown in FIG. 12, walls 171, 173, 175 generally correspond to walls 31, 33, 35 (FIG. 8), respectively, but the welded edge to provided with a flange or bead 179 which will mechanically reinforce the bond and assist in preventing any sepaaration of welded layers.

It should be noted that certain flowable substances may corrode metal foil when contact is maintained during an extended period of time. For example, some catalysts tend to corrode aluminum foil. In cases of such type, the flowable substance may be sealed in a small auxiliary rupturable pouch and the latter may beplaced in a collapsible capsule, e.g., in the chamber S of capsule 30 (FIG. 8), instead of depositing the flowable substance directly in the respective chamber. Contact between the flowable substance and the walls of the capsule proper will thus be avoided during storage. If suitable, the auxiliary pouch may consist of plastics.

Various other modifications and changes may be made without departing from the scope of the invention as defined in the appended'claims.

In theclaims, the term first substance refes to a material which is preferably pulverulent, while at least one and preferably both of the materials referred to as second and third substances" are flowable. The term "lenticular as used herein refers to a biconvex form as well as to a shape which is convex at one side and flat or concave at the opposite side.

What is claimed is:

1. In a receptacle for initially separately storing and subsequently mixing a first substance and at least a second and third substance tomake a product such as a dental preparation ready forum, at least one of said second and third substances being flowable, and said substances being capable of causing a reaction when mixed with each other; a base member having a first chamber therein, said chamber receiving said first substance; a dividing wall carried by and extending generally across said base member and having an opening therein, said dividing wall having an upper and a lower face when said receptacle is in upright position, said lower face of the dividing wall limiting said first chamber; means forming a unit with said dividing wall and having a cavity therein, said cavity having an inner end adjacent said upper face of the dividing wall and an outer end remote therefrom; a collapsible capsule consisting of flexible sheet material and positioned in said cavity, said capsule including a frangible top wall and a frangible bottom wall abutting said upper face of the dividing wall, at least a second chamber being formed between said top and bottom walls of the capsule and receiving said second substance; a hollow ram inserted in said cavity from said outer end of the latter and accommodating a third chamber receiving said third substance, said hollow ram having a frangible bottom adjacent said top wall of the capsule and an outer end remote therefrom; and a piston inserted in said hollow ram from said outer end thereof, said piston closing said third chamber towards the outside and being movable in said hollow ram to exert pressure directly upon said third and indirectly upon said second substance and thereby to break said frangible bottom of the ho]- low ram and said frangible top and bottom walls of the capsule so as to connect said chambers and permit passage of at least said second and third substancesfrom said second and third chambers through said opening of the dividing wall into said first chamber for admixture to said first substance.

2. A receptacle as defined in claim 1, including a weakened breakable portion provided in said bottom wall of the capsule and aligned with said opening the dividing wall; a further weakened, breakable portion in said top wall of the capsule; and -an additional weakened, breakable portion in said bottom of the hollow ram; said further and additional breakable portions being aligned with each other to facilitate flow after rupture of said portions.

3. A receptacle as defined in claim 1, wherein said hollow ram includes a sleeve-like portion connected to said bottom thereof.

4. A receptacle as defined inclaim 1, including abutment means arranged on said base member and adapted to engage said unit for preventing movement of said unit relative to said base member in the direction towards said first chamber when said unit is in a predetermined position relative to said base member.

5. In a receptacle for initially separately storing and subsequently mixing a first substance and at least a second and a third substance to make a product such as a dental preparation ready for use, at least one of said second and third substances being flowable, and said substances being capable of causing a reaction when mixed with each other; a base member having a first chamber therein, said chamber receiving said first substance; a'dividing wall extending generally across said base member and having an opening therein, one lateral face of said dividing wall limiting said first chamber; hollow means carried by said base member and forming a cavity adjacent to the other lateral face of said dividing wall; and insertable means positioned in said cavity and forming at least a second and a third chamber receiving said second and third substances, respectively, at least the major portion of said third chamber being-disposed above said second chamber when said receptacle is in upright position; frangible means on said insertablemeans, said frangible means intially limiting at least said second and third chambers and upon rupture forming a passageway leading from said third chamber through said second chamber to said opening in the dividing wall and into said first chamber; at least one of said hollow means and insertable means being operable to cause rupture of said frangible means and permit flow of said second and third substances through said passageway into said first chamber for admixture to said first substane, said third substance rinsing substantially the entire second chamber when passing therethrough.

1.! l 1.! I i F ORM PO-IOSO (10-69) U ITED STATES PATENT FFIcE CERTIFICATE OF CORRECTION Dated October 2, 1973 Patent No. 3, 762 540 ErwinBaumann, Gerhard Beham, Frick Hansjorg Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

"substane" should be Claim 5, column 16, line 65,

-substance Signed and sealed this 2nd day of April 197M.

(SEAL) Attestz- EDWARD I LFLE'IUHERJR. C. MARSHALL DANN Commissioner of Patents Attesting Officer USCOMM-DC 6O376-P' u.s, GOVERNMENT PRINTING OFFICE: 1909 0-365-1 

1. In a receptacle for initially separately storing and subsequently mixing a first substance and at least a second and third substance to make a product such as a dental preparation ready for use, at least one of said second and third substances being flowable, and said substances being capable of causing a reaction when mixed with each other; a base member having a first chamber therein, said chamber receiving said first substance; a dividing wall carried by and extending generally across said base member and having an opening therein, said dividing wall having an upper and a lower face when said receptacle is in upright position, said lower face of the dividing wall limiting said first chamber; means forming a unit with said dividing wall and having a cavity therein, said cavity having an inner end adjacent said upper face of the dividing wall and an outer end remote therefrom; a collapsible capsule consisting of flexible sheet material and positioned in said cavity, said capsule including a frangible top wall and a frangible bottom wall abutting said upper face of the dividing wall, at least a second chamber being formed between said top and bottom walls of the capsule and receiving said second substance; a hollow ram inserted in said cavity from said outer end of the latter and accommodating a third chamber receiving said third substance, said hollow ram having a frangible bottom adjacent said top wall of the capsule and an outer end remote therefrom; and a piston inserted in said hollow ram from said outer end thereof, said piston closing said third chamber towards the outside and being movable in said hollow ram to exert pressure directly upon said third and indirectly upon said second substance and thereby to break said frangible bottom of the hollow ram and said frangible top and bottom walls of the capsule so as to connect said chambers and permit passage of at least said second and third substances from said second and third chambers through said opening of the dividing wall into said first chamber for admixture to said first substance.
 2. A receptacle as defined in claim 1, including a weakened breakable portion provided in said bottom wall of the capsule and aligned with said opening the dividing wall; a further weakened, breakable portion in said top wall of the capsule; and an additional weakened, breakable portion in said bottom of the hollow ram; said further and additional breakable portions being aligned with each other to facilitate flow after rupture of said portions.
 3. A receptacle as defined in claim 1, wherein said hollow ram includes a sleeve-like portion connected to said bottom thereof.
 4. A receptacle as defined in claim 1, including abutment means arranged on said base member and adapted to engage said unit for preventing movement of said unit relative to said base member in the direction towards said first chamber when said unit is in a predetermined position relative to said base member.
 5. In a receptacle for initially separately storing and subsequently mixing a first substance and at least a second and a third substance to make a product such as a dental preparation ready for use, at least one of said second and third substances being flowable, and said substances being capable of causing a reaction when mixed with each other; a base member having a first chamber therein, said chamber receiving said first substance; a dividing wall extending generally across said base member and having an opening therein, one lateral face of said dividing wall limiting said first chamber; hollow means carried by said base member and forming a cavity adjacent to the other lateral face of said dividing wall; and insertable means positioned in said cavity and forming at least a second and a third chamber receiving said second and third substances, respectively, at least the major portion of said third chamber being disposed above said second chamber when said receptacle is in upright position; frangible means on said insertable means, said frangible means intially limiting at least said second and third chambers and upon rupture forming a passageway leading from said third chamber through said second chamber to said opening in the dividing wall and into said first chamber; at least one of said hollow means and insertable means being operable to cause rupture of said frangible means and permit flow of said second and third substances through said passageway into said first chamber for admixture to said first substane, said third substance rinsing substantially the entire second chamber when passing therethrough. 